In every industry, computers are coming into everyday use. These computers are used to write and read data to large storage devices to store and recall the tremendous volumes of information that are increasingly required by small and large businesses.
Storage devices in all computer systems are susceptible to failures. This is especially true in disk drives where failures can be caused by temperature variations, head crashes, motor failure, controller failure, and changing voltage conditions. Modern computer systems for critical systems, such as airport controllers, require a fault-tolerant data storage system, for protecting data against disk drive failure.
One approach to meeting this need is to provide a redundant array of independent disks (RAID) system operated by a disk array controller (controller). RAID technology developed to provide for reliable storage of data on multiple storage devices. RAID allows the combining of two or more storage devices, such as disk drive systems, to create an array of storage devices.
Hardware or software implementation allows the multiple storage devices to be treated as one logical storage device. Data is stored redundantly in various ways to enhance data integrity and availability. RAID sub-systems provide cost-effective solutions for storage strategies. RAID systems are also able to provide improved data transfer rates and throughput of data.
Redundant array of independent disks (RAID) technology provides various ways to use multiple storage devices to increase availability and performance. A number of RAID levels have been defined in which each level provides unique throughput and fault tolerance characteristics. Several RAID levels provide fault tolerance such that if one of the multiple storage devices fails, then access to all data stored on the array is still available. The failed storage device may be replaced or repaired while the array is still usable and accessible as though there had been no failure.
Thus, a need still remains for a redundant array of independent disks system with inter-controller communication to provide a fault-tolerant data storage system. In view of data reliability, it is increasingly critical that answers be found to these problems. In view of the ever-increasing commercial competitive pressures, along with growing consumer expectations and the diminishing opportunities for meaningful product differentiation in the marketplace, it is critical that answers be found for these problems. Additionally, the need to reduce costs, improve efficiencies and performance, and meet competitive pressures adds an even greater urgency to the critical necessity for finding answers to these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.